Apparatus for processing numerical control program

ABSTRACT

A numerical control program in the form of a high-level language on a paper tape (14) is converted in its entirety to a machine language by using a compiler stored in a compiler cassette (19). The converter program is then stored in a RAM area (12) of a numerical control system (numerical control program storage area), and thereafter written as the machine language into a new ROM cassette (18) by writing means such as a ROM writer (17). The ROM cassette (18) is detachable from the numerical control system and can be carried away. For executing a numerical control process, the ROM cassette (18) is attached to the numerical control system, and the numerical control program stored as the machine language in the ROM cassette (18) is transferred to the numerical control system, after which the numerical control program is executed.

TECHNICAL FIELD

The present invention relates to an apparatus for processing a numericalcontrol program for controlling a numerical control system.

BACKGROUND ART

Recent numerical control systems which mostly incorporate computers arecalled computerized numerical control (CNC) systems. The CNC system hasa microprocessor and other components such as a tape reader, switches,lamps, and a servomechanism which are connected to the microprocessorthrough a bus line extending therefrom. The states of all of thesecomponents are detected from time to time by the microprocessor, whichapplies commands to these components to effect various operationsaccording to a numerical control program. The numerical control programis ordinarily stored on a punched tape. Before the CNC system isoperated, the punched tape is fed through the tape reader which thentransfers the program from the punched tape into a random-access memory(RAM) in the CNC system. In some CNC systems, a numerical controlprogram stored in a read-only memory (ROM) in the CNC system istransferred into the RAM.

Thereafter, numerically controlled operation is effected according tothe numerical control program stored in the RAM.

The numerical control program in the punched tape or the RAM is storedin the form of a numerical control high-level language such as FAPT.Each time the numerical control program is executed, it is usuallyconverted to a machine language applicable to the numerical controlsystem by using a compiler stored in the numerical control system.

According to the prior art, when the numerical control program isexecuted, a tape editing area in the numerical control program must beused, and the processing time includes a time required to compile thenumerical control program. Thus, the numerical control program cannotquickly be executed. Where a paper tape is employed to store a numericalcontrol program, difficulty is experienced in keeping secrets since thenumerical control program can easily be read by a human being.

SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide anapparatus for processing a numerical control program, which willeliminate the aforesaid problem, and more particularly to an apparatusfor processing a numerical control program, wherein secrecy is providedby storing a numerical control program in a ROM, a memory is protectedagainst destruction, and the numerical control program can quickly beprocessed.

To achieve the above object, there is provided in accordance with thepresent invention an apparatus for processing a numerical controlprogram for controlling a numerical control system, comprising acompiler cassette detachable from the apparatus and storing therein acompiler for converting a numerical control program in the form of ahigh-level language to a machine language, converting means forconverting, with the compiler, a numerical control program input to thenumerical control system in the form of a high-level language to amachine language applicable to the numerical control system, a ROMcassette detachable from the apparatus and having a read-only memorytherein, writing means for writing the numerical control program asconverted to the machine language into the read-only memory in the ROMcassette, and control means for controlling the numerical control systemaccordign to the numerical control program stored in the read-onlymemory in the ROM cassette.

BRIEF DESCRIPTION OF THE DRAWING

The FIGURE is a block diagram of an embodiment of the present invention,showing a numerical control system in the form of a computer connectedto peripheral devices.

DESCRIPTION OF THE PREFERRED EMBODIMENT

An embodiment of the present invention will hereinafter be described inspecific detail with reference to the drawing.

The FIGURE is a block diagram of an embodiment of the present invention,showing a numerical control system (CNC) in the form of a computerconnected to peripheral devices.

Denoted in the FIGURE at 10 is a central processing unit (CPU), 11 aread-only memory (ROM) storing an operating system and invariable data,12 a random-access memory (RAM) for temporarily storing data whennumerical control operation is effected and for storing a numericalcontrol (NC) program which is input from an external source, and 13 atape reader for reading a stored NC program from a paper tape 14. The NCprogram stored in the paper tape 14 is stored in the form of ahigh-level language for the NC program, such as FAPT. Designated at 15is a CRT display unit for displaying machining data while NC machiningis being effected and the NC program being edited, 16 a keyboard, and 17a ROM writer associated with the numerical control system for writingthe NC program as converted to a machine program (described later) intoa ROM cassette 18. The ROM cassette 18 is a cassette comprising a bubblememory or an EPROM and detachable from the numerical control system.When attached to the numerical control system, the ROM cassette 18 isconnected to a bus line and controlled by the CPU 10. Denoted at 19 is acompiler cassette having a ROM storing a compiler for converting the NCprogram expressed by a high-level language such as FAPT to a machineprogram. Like the ROM cassette 18, the compiler cassette 19 is acassette comprising a bubble memory or an EPROM and detachable from thenumerical control system. When attached to the numerical control system,the comiler cassette 19 is connected to the bus line and controlled bythe CPU 10.

Designated by the reference numeral 20 is a servomotor of a machine toolor a robot which is controlled by the NC system. A rotational speedsignal of the servomotor 20 is fed from a tachometer generator 21 backto a speed control unit 22, and an angular position signal of theservomotor 20 is fed from a position detector 23 back to a positioncontrol unit 24. Denoted at 25 is a bus.

While there are various other devices connected to the bus of thenumerical control (CNC) system, they will not be described for brevity.

Operation of the embodiment of the present invention will be describedbelow.

The contents of an NC program expressed by a high-level language such asFAPT and stored in a storage medium such as the paper tape 14 are firstconverted to a format which can easily be executed by the numericalcontrol (CNC) system, by using a compiler stored in the compilercassette 19 attached to the numerical control (CNC) system. Theconversion to such a format is, for example, the conversion from thecontents of the NC program to a machine language.

The contents of the NC program as converted to the format which caneasily be executed by the numerical control (CNC) system are temporarilystored in the RAM 12, and then read out and written into the ROM in theROM cassette 18 by the ROM writer 17. As many ROM cassettes 18 asdesired can be copied by such a process. The above editing process isexecuted while putting the numerical control (CNC) system in an editingmode.

For the numerical control (CNC) system to execute a numerical controlprocess, the ROM cassette 18 which stores the numerical control programas converted by the compiler cassette 19 to the format that can easilybe executed by the numerical control (CNC) system is connected to thenumerical control (CNC) system, as indicated by the dotted lines, andthe stored NC program is read out and stored into the RAM 12.Thereafter, the NC process is executed according to the NC programstored in the RAM 12.

With the present invention, as described above, the numerical controlprogram is converted to the format which can easily be executed fornumerical control, by using the memory device storing the compiler, andthe converted program is stored into the ROM cassette by the ROMcassette writer. Subsequently, the numerical control program is executedby employing the ROM cassette. Accordingly, program secrecy is provided,and the numerical control program can quickly be executed.

The present invention is applicable to not only numerically controlledmachine tools, but also all devices controlled by numerical controlsystems, such as a device for controlling an industrial robot, a devicefor controlling an electric discharge machine tool, and the like. Thecompiler cassette and the ROM cassette can be replaced with floppydiscs, portable magnetic discs, magnetic tape cassettes, or the likethrough a mere design change. While the high-level language is convertedto the machine language by the numerical control system having the ROMwriter according to the present invention, such conversion may beeffected by a numerical control program.

I claim:
 1. An apparatus for processing a numerical control program forcontrolling a numerical control system, comprising:compiler cassettemeans for compiling data and being detachable from the apparatus andincluding converting means for converting a numerical control programinput to the numerical control system in the form of a high-levellanguage to a machine language applicable to the numerical controlsystem; ROM cassette means, detachable from the apparatus and having aread-only memory, for storing programs; writing means for writing thenumerical control program as converted to the machine language by saidcompiler cassette into the read-only memory of said ROM cassette means;and control means for controlling the numerical control system accordingto the numerical control program stored in the read-only memory of saidROM cassette means.
 2. An apparatus according to claim 1, wherein saidcompiler cassette means includes a bubble memory.
 3. An apparatusaccording to claim 1, wherein said compiler cassette means includes anEPROM.
 4. An apparatus according to claim 1, wherein the read-onlymemory of said ROM cassette means comprises a bubble memory.
 5. Anapparatus according to claim 1, wherein the read-only memory of said ROMcassette means comprises an EPROM.